When accelerating in my 4x4 sapphire im getting a backfire with lots of smoke which sometimes cuts the engine out. This happens at around 3500 to 4000 revs (just about when the boost comes on) and in every gear. Sometimes when the engine cuts out it wont start again straight away and needs turning over for a couple of mins. Apart from this the car runs perfectly with no other problems what so ever!!

Unfortunately im out of work at the moment and cant afford to see a specialist so wondering if there was anything i could look at myself. Any help would be very much appreciated

 

ignition or lack of fuel.
I had lack of fuel problem in my mustang when it would (atempt) to get into the power. The computer starts to adjust timing to give more power and prevent detonation. However the jets were wrong (not rich enough) and the car would ping and the computer would kill the timing resulting in a nasty backfire and other un fun stuff.

I know it is not Cosworth, but may somehow help. I am not all to familiar with the coswrorths.
TF

 

Sounds like you could be onto something there When i bought the car i was told that it had subtle engine modifications which included a chip. Ive had a look at the chip and it says COS4x4PH1, perhaps some of the more hardcore cosworth experts might be able to shed more light on as to what the chip is. The only thing i was able to liken it too is the superchips phase 1 chip which provides 310bhp. If this is the case maybe this is causing the problem as i still have the standard blue injectors Or on the other hand i could be completley wrong

 

I had a similar problem when i picked up my cosworth.I bought it from a dealer who had got the yts boy to clean the engine with a jet wash.In the end i found that water was in the ignition amplifier terminal on the inner wing.I blew it out and wd40'd it.It has been fine ever since.If this is the case with yours then check all the connectors for moisture and wd40 them anyway.Hope this helps.

 

This sounds very similar to a problem am experiencing with our 4x4 at the moment, it doesn't backfire or smoke (well anymore than cossies do) but it does cut out for no reason and have problems starting again - the connector on the inner wing has been suggested, so we'll try that and see how go, trouble is it seems to be an intermitment problem so wont know for sure if fixed it

Z

 

Dont know why it should smoke but when it backfires when you come up on boost it is normally one of two things! 1. your spark plug gap is to big and the boost blows it out or 2. theres water in your crankshaft sensor plug which is at the front of your engine and seems to catch water for some reason!

 

may be worth checking the wires that go to the coil. if it not a good connection then it may miss and back in the exhaust when the unburnt fuel hits the hot manifold

happened to me a few times

wortha try